CVE-2026-21857

6.5 MEDIUM
Published: January 07, 2026 Modified: January 20, 2026
View on NVD

Description

REDAXO is a PHP-based content management system. Prior to version 5.20.2, authenticated users with backup permissions can read arbitrary files within the webroot via path traversal in the Backup addon's file export functionality. The Backup addon does not validate the `EXPDIR` POST parameter against the UI-generated allowlist of permitted directories. An attacker can supply relative paths containing `../` sequences (or even absolute paths inside the document root) to include any readable file in the generated `.tar.gz` archive. Version 5.20.2 fixes this issue.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://github.com/redaxo/redaxo/releases/tag/5.20.2
Source: security-advisories@github.com
Release Notes
https://github.com/redaxo/redaxo/security/advisories/GHSA-824x-88xg-cwrv
Source: security-advisories@github.com
Exploit Vendor Advisory
https://github.com/redaxo/redaxo/security/advisories/GHSA-824x-88xg-cwrv
Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
Exploit Vendor Advisory

3 reference(s) from NVD

Quick Stats

CVSS v3 Score
6.5 / 10.0
EPSS (Exploit Probability)
0.0%
7th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

redaxo